Extreme events in epileptic EEG of rodents after ischemic stroke

Extreme events are observed on electroencephalographic (EEG) recordings of rodents with induced ischemic stroke. These events represent themselves as post-stroke epileptic seizures in the form of spontaneous high-amplitude oscillations, which appear during the first 2–3 h after induced focal cerebral ischemia. The analysis of the EEG time-frequency structure reveals these extreme events as a sharp sudden growth of the wavelet energy in a particular frequency band, while the energy in the resting part of the power spectrum remains normal. The distinguished features of the extreme events are used for detection and quantification of the pathological brain activity.     

Local Pairs in High-Temperature Superconductors: Proof of Existence and Manifestation in Heat Transfer

The comparison of the temperature anomalies of the charge carrier density in high-temperature cuprate superconductor Bi_1.6(Pb_0.4)Sr₂Ca₂Cu₃O_{10 + x} and features of the parameters of the crystal lattice has demonstrated that the concept of pairing of single-particle hole excitations on the Fermi surface into singlet pairs is realistic. Anomalies of the thermal conductivity correlated with the presence of paired quasiparticle states have been revealed. Both types of anomalies indicate the existence of three stages of the temperature evolution of a pseudogap.     

Hydrogen Permeability of a Foil of Pd–Ag Alloy Modified with a Nanoporous Palladium Coating

Thin films with the composition Pd–23% Ag are obtained via magnetron sputtering. The magnetron sputtering of Pd–50% Zn films with subsequent diffusion annealing and etching of the active component is used to modify the surfaces of palladium–silver films to improve their hydrogen permeability. Modifying the surfaces of the resulting Pd–Ag films using a nanoporous palladium coating with a predominant distribution of particles ranging from 0 to 50 nm allows a hydrogen flux density of up to 0.4 mmol s^?1 m^?2 to be achieved for sufficiently thin palladium membranes (<10 μm) under conditions of low temperature (<90°C) and pressure (<0.6 MPa). Experimental evidence is gathered that under these conditions, the velocity of hydrogen transport is limited by dissociative–associative processes at membrane boundaries and can be greatly (by an order of magnitude) increased, due to acceleration of the limiting stage of the process via the formation of a palladium nanoporous coating on the film’s surface.